X-Wind Landing Techniques
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X-Wind Landing Techniques
I'm seeking some advice on cross-wind landing techniques.
The following video is a series of 4 clips taken from Boeing, probably to test X-wing handling capabilities of the 777 and 747SP.
http://www.youtube.com/watch?v=kWEVdEpf3yc
1. In the first clip (777), would you agree that the pilot was a little late in applying right rudder to align the aircraft down the runway centreline? (BTW, I'm not being critical of the pilot .... for all I know, Boeing may have been testing the tolerances of the main landing gear to such conditions)
2. Would you agree that the third clip (777) in the series is the correct crab technique with correct application of right rudder and left aileron into the wind on touch down?
TIA.
The following video is a series of 4 clips taken from Boeing, probably to test X-wing handling capabilities of the 777 and 747SP.
http://www.youtube.com/watch?v=kWEVdEpf3yc
1. In the first clip (777), would you agree that the pilot was a little late in applying right rudder to align the aircraft down the runway centreline? (BTW, I'm not being critical of the pilot .... for all I know, Boeing may have been testing the tolerances of the main landing gear to such conditions)
2. Would you agree that the third clip (777) in the series is the correct crab technique with correct application of right rudder and left aileron into the wind on touch down?
TIA.
Why do it if it's not fun?
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Minga,
Great video, have seen it many times before but never thought to analyze it in this way. My comments assume that you are relating this to teaching a student to land a light aircraft (due to the fact that you've posted in the Instructors forum) - if this is not correct, then I apologise.
Yes, I agree. But I would also add that I have done many landings like this (normally when waiting to see whether the student would kick it straight, and only kicking it straight myself when it's clear the student isn't going to) in light aircraft, and never found it to be a problem. In any tricycle aircraft, the aircraft will tend to straighten itself out after the main wheels touch, anyway, which makes this a fairly "easy" way to land an aircraft, although probably not the kindest on the gear. (However, don't try it in a tail-dragger!)
Again, yes. But I'd also add that it is extremely difficult to get this right in any light aircraft. In a jet, the mass (and therefore the momentum) is sufficiently high that the aircraft will remain on the centre-line for some time after rudder is applied. In a light aircraft, as soon as you start applying rudder, the aircraft will begin to drift off the centre-line. So a crabbed approach in a light aircraft will almost always end up becoming a wing-low landing (even if not until the very last moment) unless the timing really is absolutely spot on. (In fact, in the clip, you can see the landing is slightly wing-low as the into-wind wheel touches slightly before the other main.)
It's also interesting to compare a jet's landing with that of a light aircraft. In the jet, there is a flare, but no hold-off where the aircraft is flown level before touching down. This is different to a light aircraft, where the student should be taught to fly the aircraft level above the runway until it lands itself. In a true crabbed landing in a light aircraft, the rudder will not be applied until the aircraft is in level flight a few feet above the runway - something which obviously can't be seen in the clips.
This is just my opinion - x-wind landings is one of those areas where 10 different pilots will give you 11 different ways of doing it, so I'm sure my reply will spark some debate.
FFF
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Great video, have seen it many times before but never thought to analyze it in this way. My comments assume that you are relating this to teaching a student to land a light aircraft (due to the fact that you've posted in the Instructors forum) - if this is not correct, then I apologise.
In the first clip (777), would you agree that the pilot was a little late in applying right rudder to align the aircraft down the runway centreline?
2. Would you agree that the third clip (777) in the series is the correct crab technique with correct application of right rudder and left aileron into the wind on touch down?
It's also interesting to compare a jet's landing with that of a light aircraft. In the jet, there is a flare, but no hold-off where the aircraft is flown level before touching down. This is different to a light aircraft, where the student should be taught to fly the aircraft level above the runway until it lands itself. In a true crabbed landing in a light aircraft, the rudder will not be applied until the aircraft is in level flight a few feet above the runway - something which obviously can't be seen in the clips.
This is just my opinion - x-wind landings is one of those areas where 10 different pilots will give you 11 different ways of doing it, so I'm sure my reply will spark some debate.
FFF
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hehehe.
Maybe im the odd one out then.
To be honest I see the wing-down AND crab approaches with last second kick round AND the combined methods as ALL one of the same thing. The question is simply a matter of WHEN you put in the controls. In most cases I find that crab method has the students failing to apply enough rudder or aileron.
Liek I said maybe im the odd one out in the crab vs wing-down wars.
Maybe im the odd one out then.
To be honest I see the wing-down AND crab approaches with last second kick round AND the combined methods as ALL one of the same thing. The question is simply a matter of WHEN you put in the controls. In most cases I find that crab method has the students failing to apply enough rudder or aileron.
Liek I said maybe im the odd one out in the crab vs wing-down wars.
Why do it if it's not fun?
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To be honest I see the wing-down AND crab approaches with last second kick round AND the combined methods as ALL one of the same th
Crab technique - the wings are level for the landing. Timing is everything. Aileron is used to counteract the secondary effect of rudder, but not to bank the aircraft.
Wing-low technique - the aircraft is aligned with the runway for some of the approach. I tend to find that if a student struggles to learn the crabbed technique, they might find the wing-low technique easier. Or, in many cases, after seeing the wing-low technique, the crab technique makes more sense to them and becomes easier. Wing-low used to be my preferred technique as a low-hours pilot, and still is on light tail-draggers (on the rare occassions I get to fly them), but if you apply the controls too early you need to make corrections as the wind changes on the approach and on entering ground effect.
Combination - probably the easiest technique, since it doesn't need the exact timing of the crab technique nor the changes during the approach of the wing-low technique. It is basically the same as the wing-low technique except that the aircraft is not aligned with the runway until in ground effect. Not really suitable for short-field landings where the time in ground effect is very short due to the lower approach speeds - although most attempts at crabbed landings in light aircraft turn into combination landings anyway due to the fact that none of us can get the timing perfect every time.
A clear distinction there, IMHO. The controls are the same in each case, that's true. But the timing, the amount of control required, and even the purpose of using the control (aileron is used to roll the aircraft for a wing-low approach but to counteract secondary effect of rudder in a crabbed approach) is very different.
FFF
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Looked more like a forward slip ,than a sideslip to compensate for X-wind on landing.
The tires will not last landing like that ,The airplane should always be landed in the direction of travel when traction on the runway is assured.
Always fly the airplane until you tie it down
The tires will not last landing like that ,The airplane should always be landed in the direction of travel when traction on the runway is assured.
Always fly the airplane until you tie it down
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Is this how the crap creeps into light aircraft pilot technique?
I'm seeking some advice on cross-wind landing techniques.
The following video is a series of 4 clips taken from Boeing, probably to test X-wing handling capabilities of the 777 and 747SP.
http://www.youtube.com/watch?v=kWEVdEpf3yc
1. In the first clip (777), would you agree that the pilot was a little late in applying right rudder to align the aircraft down the runway centreline? (BTW, I'm not being critical of the pilot .... for all I know, Boeing may have been testing the tolerances of the main landing gear to such conditions)
2. Would you agree that the third clip (777) in the series is the correct crab technique with correct application of right rudder and left aileron into the wind on touch down?
TIA.
The following video is a series of 4 clips taken from Boeing, probably to test X-wing handling capabilities of the 777 and 747SP.
http://www.youtube.com/watch?v=kWEVdEpf3yc
1. In the first clip (777), would you agree that the pilot was a little late in applying right rudder to align the aircraft down the runway centreline? (BTW, I'm not being critical of the pilot .... for all I know, Boeing may have been testing the tolerances of the main landing gear to such conditions)
2. Would you agree that the third clip (777) in the series is the correct crab technique with correct application of right rudder and left aileron into the wind on touch down?
TIA.
My understanding is that the X-wind landing technique for a heavy (as demonstrated in these video clips - ie crab throughout the flare and touchdown) is quite differenct from that which is normally used in lighties.
If so, the discussion in this thread is irrelevant!
R
Nope - I taught the 'crab' technique in both the Bulldog and the VC10. The only real difference was that 'de-crabbing' in the flare with a swept wing aeroplane will cause roll in the same direction, so care has to be taken to anticipate the effect and to be ready for it.
And you NEVER 'kick' aeroplanes!
And you NEVER 'kick' aeroplanes!
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Rat****,
Think about it. Why would you not lay off the crab angle during the hold off?
The side loads on the undercarriage are huge if you get it wrong, not to mention the possibility of ripping the tyres off of the rims.
The chances are these days the company will issue you with a warning letter.
Think about it. Why would you not lay off the crab angle during the hold off?
The side loads on the undercarriage are huge if you get it wrong, not to mention the possibility of ripping the tyres off of the rims.
The chances are these days the company will issue you with a warning letter.
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There is another method I have seen used whan sitting beside pilots in what you call 'heavies' that is land with most of the drift on, amazing how many experienced pilots do this!
On cat 3 landings on one swept back wing aircraft i operated you could feel the auto pilot using the wing down method over the threshold.
the aim is to touch down with zero drift close to the centre line and roll out following it, the technique you use in a light aircraft should be what you feel happy with, if you miss with de-crabbing go for wing down
On cat 3 landings on one swept back wing aircraft i operated you could feel the auto pilot using the wing down method over the threshold.
the aim is to touch down with zero drift close to the centre line and roll out following it, the technique you use in a light aircraft should be what you feel happy with, if you miss with de-crabbing go for wing down
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Hi. I am not an instructor but I am a PPL just curious about this topic.
When you say...'application of rudder to bring the nose into line with the intended landing direction' do you mean that you crab the a/c down the approach using co-ordinated controls and then once in the flare straighten the a/c up with use of rudder?
When I first learnt to fly I was taught to do that however later on in my flying I was told to fly the a/c down the approach with crossed controls, i.e. X-wind from the left, left wing down with right rudder to keep the nose pointing in the direction of the runway.
Which technique is mostly taught and which is the better technique? If there is such a thing as a better technique!
Cheers all
When you say...'application of rudder to bring the nose into line with the intended landing direction' do you mean that you crab the a/c down the approach using co-ordinated controls and then once in the flare straighten the a/c up with use of rudder?
When I first learnt to fly I was taught to do that however later on in my flying I was told to fly the a/c down the approach with crossed controls, i.e. X-wind from the left, left wing down with right rudder to keep the nose pointing in the direction of the runway.
Which technique is mostly taught and which is the better technique? If there is such a thing as a better technique!
Cheers all
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Hi. I am not an instructor but I am a PPL just curious about this topic.
When you say...'application of rudder to bring the nose into line with the intended landing direction' do you mean that you crab the a/c down the approach using co-ordinated controls and then once in the flare straighten the a/c up with use of rudder?
When you say...'application of rudder to bring the nose into line with the intended landing direction' do you mean that you crab the a/c down the approach using co-ordinated controls and then once in the flare straighten the a/c up with use of rudder?
The first approach you talk about is crab method, the second wing-down. Is there a better method? I find combination technique - as described in above posts works best for my students and I use that myself as well...and it gets me down wings level in most circumstances.
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Nw, I re-read and can see where you were going with that one!
Ah right, well its just when I did what I was taught from the outset with another instructor, I got a roasting and told that I was going in the wrong direction and to point the nose in the direction of the final approach track with the wing down to counter the drift. To me though this just sounded daft as I was flying with crossed controls all the way from the turn on to final to the moment I vacated the runway! I was always taught to fly with co-ordinated controls untill on the ground or just before/after. Anyway I'll give the combination of the 2 a try and see where that gets me!
Thanks
Ah right, well its just when I did what I was taught from the outset with another instructor, I got a roasting and told that I was going in the wrong direction and to point the nose in the direction of the final approach track with the wing down to counter the drift. To me though this just sounded daft as I was flying with crossed controls all the way from the turn on to final to the moment I vacated the runway! I was always taught to fly with co-ordinated controls untill on the ground or just before/after. Anyway I'll give the combination of the 2 a try and see where that gets me!
Thanks
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Put yourself in the position of a passenger when flying a cross controlled slipping final approach.
How long would it be before you wondered why the pilot was making you feel like you were going to fall sideways out of the airplane?
How long would it be before you wondered why the pilot was making you feel like you were going to fall sideways out of the airplane?
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Yeah thats a good point, I presume that was one reason why I was taught the crabbing method. Also, what would be the effect of having crossed controls at the stall? (short of me trying it at height) For instance, you got distracted on the approach, passengers being sick and your speed started to drop off, eventually you stall...
Assume you have a Port crosswind component, you would have right rudder and left wing down. Right rudder would make the a/c yaw to the right but would the left wing down situation prevent a spin or would it have an adverse effect? Would the left wing be producing more lift than the right (before the right yawing motion was started), if this was the case surely this would make the spin situation worse as it would be acting in the same direction as the yawing motion? Also would a/c type have an effect?
I could of course be reading far too much into this, I hope that made sense, any explanation would be greatly received!
Assume you have a Port crosswind component, you would have right rudder and left wing down. Right rudder would make the a/c yaw to the right but would the left wing down situation prevent a spin or would it have an adverse effect? Would the left wing be producing more lift than the right (before the right yawing motion was started), if this was the case surely this would make the spin situation worse as it would be acting in the same direction as the yawing motion? Also would a/c type have an effect?
I could of course be reading far too much into this, I hope that made sense, any explanation would be greatly received!
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Well Commanche let me try and make it simple.
Do you side slip to correct for drift on a x/country?
Do you side slip cross wind, down wind and on base leg to correct for drift?
After you think that over maybe you will come to the conclusion that side slipping all the way down final ( finals in Britain .
) is not necessary for holding the center line.
Chuck E.
Do you side slip to correct for drift on a x/country?
Do you side slip cross wind, down wind and on base leg to correct for drift?
After you think that over maybe you will come to the conclusion that side slipping all the way down final ( finals in Britain .
) is not necessary for holding the center line.Chuck E.
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Chuck E, yeah I fully understand that, thats the point i was making that I was taught not to sideslip and not use crossed controls on final, but an instructor told me that this was the correct method. I would always, and have always been flying approaches with co-ordinated use of controls as that is what I was taught and I think thats what I shall carry on doing.
Cheers
Cheers